Comparison of Direct Digital Mammography, Computed Radiography, and Film-Screen in the French National Breast Cancer Screening Program

To compare screen-film mammography with digital mammography in a breast cancer screening program, with a focus on the clinical relevance of detected cancers. The study was approved by the regional medical ethics review board. Informed consent was not required. Before the nationwide transition to digital mammography in the Dutch biennial screening program, the performance of digital mammography was studied in three screening regions. For initial screening examinations, mediolateral oblique and craniocaudal views were obtained of each breast. In subsequent examinations, the mediolateral oblique view was standard. A craniocaudal view was added if indicated. Screening outcomes obtained with screen-film mammography and digital mammography, including radiologic and pathologic characteristics, were compared for initial and subsequent examinations. A total of 1,198,493 screening examinations were performed between 2003 and 2007. Recall was indicated in 18 896 cases (screen-film mammography: 2.6% at initial examinations, 1.3% at subsequent examinations; digital mammography: 4.4% at initial examinations, 2.1% at subsequent examinations; P < .001 for both). Breast cancer was diagnosed in 6410 women (detection rate per 1000 women with screen-film mammography: 5.6 at initial examinations, 5.2 at subsequent examinations; detection rate per 1000 women with digital mammography: 6.8 at initial examinations, 6.1 at subsequent examinations; P = .02 and P < .001, respectively). Digital mammography depicted significantly more ductal carcinoma in situ (DCIS) lesions, irrespective of screening round. Invasive carcinoma was detected significantly more often in subsequent examinations, particularly when associated with microcalcifications (P = .047). The distribution of the histopathologic differentiation grades for DCIS and invasive carcinoma were similar with both modalities. However, with digital mammography more high-grade DCIS lesions were detected at subsequent examinations (P = .013). In a population-based breast screening program, the performance of digital mammography in the detection of DCIS and invasive carcinoma was substantially better than that of screen-film mammography. There is no sign of an increase in detection of low-grade DCIS lesions-indicative of possible overdiagnosis-with digital breast cancer screening. Rather, digital mammography appears to add to the detection of high-grade DCIS. © RSNA, 2012.

To (a) compare the performance of full-field digital mammography (FFDM), using hard-copy image reading, with that of screen-film mammography (SFM) within a UK screening program (screening once every 3 years) for women aged 50 years or older and (b) conduct a meta-analysis of published findings along with the UK data. The study complied with the UK National Health Service Central Office for Research Ethics Committee guidelines; informed patient consent was not required, since analysis was carried out retrospectively after data anonymization. Between January 2006 and June 2007, a London population-based screening center performed 8478 FFDM and 31 720 SFM screening examinations, with modality determined by the type of machine available at the screening site. Logistic regression was used to assess whether breast cancer detection rates and recall rates differed between screening modalities. For the meta-analysis, random-effects models were used to combine study-specific estimates, if appropriate. A total of 263 breast cancers were detected. After adjustment for age, ethnicity, area of residence, and type of referral, there was no evidence of differences between FFDM and SFM in terms of detection rates (0.68 [95% confidence interval {CI}: 0.47, 0.89] vs 0.72 [95% CI: 0.58, 0.85], respectively, per 100 screening mammograms; P = .74), recall rates (3.2% [95% CI: 2.8, 3.6] vs 3.4% [95% CI: 3.1, 3.6]; P = .44), positive predictive value (PPV) of an abnormal mammogram, or characteristics of detected tumors. Meta-analysis of data from eight studies showed a slightly higher detection rate for FFDM, particularly at 60 years of age or younger (pooled FFDM-SFM difference: 0.11 [95% CI: 0.04, 0.18] per 100 screening mammograms), but no clear modality differences in recall rates or PPVs. Within a routine screening program, FFDM with hard-copy image reading performed as well as SFM in terms of process indicators; the meta-analysis was consistent with FFDM yielding detection rates at least as high as those for SFM.

To compare full-field digital mammography (FFDM) using computer-aided diagnosis (CAD) with screen-film mammography (SFM) in a population-based breast cancer screening program for initial and subsequent screening examinations. The study was approved by the regional medical ethics review board. Informed consent was not required. In a breast cancer screening facility, two of seven conventional mammography units were replaced with FFDM units. Digital mammograms were interpreted by using soft-copy reading with CAD. The same team of radiologists was involved in the double reading of FFDM and SFM images, with differences of opinion resolved in consensus. After 5 years, screening outcomes obtained with both modalities were compared for initial and subsequent screening examination findings. A total of 367,600 screening examinations were performed, of which 56,518 were digital. Breast cancer was detected in 1927 women (317 with FFDM). At initial screenings, the cancer detection rate was .77% with FFDM and .62% with SFM. At subsequent screenings, detection rates were .55% and .49%, respectively. Differences were not statistically significant. Recalls based on microcalcifications alone doubled with FFDM. A significant increase in the detection of ductal carcinoma in situ was found with FFDM (P < .01). The fraction of invasive cancers with microcalcifications as the only sign of malignancy increased significantly, from 8.1% to 15.8% (P < .001). Recall rates were significantly higher with FFDM in the initial round (4.4% vs 2.3%, P < .001) and in the subsequent round (1.7% vs 1.2%, P < .001). With the FFDM-CAD combination, detection performance is at least as good as that with SFM. The detection of ductal carcinoma in situ and microcalcification clusters improved with FFDM using CAD, while the recall rate increased. (c) RSNA, 2009.